Design of scaffolds with natural substances holds potential in several cardiovascular applications. In this study, we have fabricated scaffold using the electrospinning technique with blends of PU and castor oil. The characterization was performed using scanning electron microscopy (SEM), Fourier transform and infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), contact angle measurement, and atomic force microscopy (AFM). Further the blood compatibility of prepared composites was calculated using APTT, PT, and hemolytic assay. SEM analysis of the fabricated scaffolds indicated random morphology of nanofibers with reduced fiber diameter of about 766 +/- 147 nm compared to pristine PU control. The FTIR confirms the interaction between PU and castor oil as identified by the formation of hydrogen bond. The developed composite rendered hydrophobic nature owing to increased contact angle and also exhibit higher thermal stability as shown by TGA. The AFM analysis revealed that the surface roughness of the nanocomposites was observed to be improved compared to control. A delay in the activation of clot was noted in activated partial thromboplastin time (APTT) and partial thromboplastin time (PT) assay revealing the anticoagulant nature of the fabricated scaffolds. Moreover, the hemolytic index of developed composites was found to be low indicating the safety of the scaffold in protecting the red blood cells from damage. The present study suggested that newly developed nanocomposite enabled tailoring of desirable characteristics matching for cardiac tissue engineering.